Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal.
Bioconjug Chem. 2011 Nov 16;22(11):2339-44. doi: 10.1021/bc200421z. Epub 2011 Oct 13.
Nucleolar targeting peptides (NrTPs), a recently developed family of cell-penetrating peptides, have been shown to be very efficient in entering cells and accumulating in their nucleoli. In this work, we have used conjugates of NrTP6 (YKQSHKKGGKKGSG) covalently linked to β-galactosidase in order to demonstrate the capacity of NrTP for intracellular delivery of large molecules. NrTP6/β-galactosidase conjugates, prepared by maleimide-based chemistry, were stable and enzymatically active on the standard 4-methylumbelliferyl β-d-galactopyranoside substrate. Their translocation into HeLa cells, monitored by β-galactosidase activity as a readout of the uptake, showed efficient cellular entry and thus demonstrated the potential of NrTPs for intracellular delivery of large-size cargos with preservation of biological activity.
核仁靶向肽（NrTPs）是最近开发的一类细胞穿透肽，已被证明在进入细胞并在其核仁中积累方面非常有效。在这项工作中，我们使用 NrTP6（YKQSHKKGGKKGSG）与β-半乳糖苷酶通过马来酰亚胺化学共价连接的缀合物，以证明 NrTP 用于将大分子递送至细胞内的能力。NrTP6/β-半乳糖苷酶缀合物通过马来酰亚胺化学制备，在标准的 4-甲基伞形酮基-β-d-半乳糖吡喃糖苷底物上稳定且具有酶活性。通过β-半乳糖苷酶活性监测其进入 HeLa 细胞的转位，作为摄取的读出，显示出有效的细胞进入，从而证明了 NrTPs 用于将大尺寸载物递送至细胞内并保持生物活性的潜力。
